A nopinone based multi-functional probe for colorimetric detection of Cu2+ and ratiometric detection of Ag.

A dual-signal probe PPN based on the natural β-pinene derivative nopinone was synthesized for the colorimetric detection of Cu2+ and ratiometric detection of Ag+. Upon the addition of Ag+, a significant fluorescence change from blue to green was observed with a low detection limit (0.86 μM). However, upon the addition of Cu2+, a significant color change from colorless to yellow was observed with a low detection limit (0.56 μM). The novel probe PPN was applied as a probe for the colorimetric detection of Cu2+ and ratiometric detection of Ag+ with a high selectivity, good sensitivity and fast response time. The detection mechanisms of probe PPN for Cu2+/Ag+ were confirmed by 1H NMR and HRMS-ESI. Besides, probe PPN could sense Cu2+/Ag+ on test strips. Additionally, probe PPN could be applied to quantitatively detect the concentration of Ag+ in water samples and image Ag+ in living cells.